1. Field of the Invention
The invention relates to a process for manufacturing cellulose formed objects, whereby a solution of cellulose is formed in the warm state in a tertiary amine N-oxide and, if necessary, water and the formed solution is cooled with air before introducing it into a coagulation bath, as well as a yarn of cellulose filaments.
2. Description of the Related Art
Such a process is described in WO 93/19230, whereby the cooling is to take place immediately after the forming. The object of this process is to reduce the stickiness of the freshly extruded formed objects so that a spinneret with a high hole density can be employed for manufacturing cellulose filaments. For cooling, the formed solution is preferably exposed to a gas stream.
A cooling of the warm formed solution already takes place as the formed solution leaves the forming tool, for instance a spinneret, in which temperatures are typically above 90.degree. C., and reaches into the so-called air gap. The area between the forming tool and the coagulation bath in which the cellulose is precipitated is referred to as the air gap. The temperature in the air gap is lower than in the spinneret, but it is significantly higher than the room temperature due to the heat radiation from the spinneret and the warm-up of the air due to the enthalpy flow of the formed objects. Due to the continuous evaporation of water which is usually used as a coagulation bath, humid warm conditions prevail in the air gap. The measure proposed in WO 93/19230, that is to cool the formed solution immediately after the forming, results in a more rapid cooling so that the stickiness of the formed solution decreases more rapidly as a result.